For passenger planes, functions including automatic flight have been realized by posture estimation, position estimation, and the like using a combination of a highly precise inertial sensor and a GPS (Global Positioning System) receiver. In recent years, decreases in the size and the cost of inertial sensors have advanced, and as a result, an inertial sensor and a GPS receiver have been mounted even on small flight vehicles to perform position estimation, posture estimation, and the like.
For example, Patent Literature 1 discloses a technology of determining a rest state of a moving body by using a combination of a GPS receiver and an inertial sensor.